Measurement of urinary and fecal steroid metabolites during the ovarian cycle in captive and wild Japanese macaques, Macaca fuscata

We measured the concentration of steroid hormones from urine, feces, and blood samples of two captive Japanese macaques, Macaca fuscata, during nonconceptive ovarian cycles to compare the patterns of the excreted steroids with those of circulating steroids. Urine and feces were analyzed for estrone conjugates (E1C) and pregnanediol-3-glucronide (PdG) using enzyme immunoassays (EIAs), while plasma was analyzed for estradiol-17beta(E2), progesterone (P), and luteinizing hormone (LH) using radioimmunoassays (RIAs). Urinary and fecal E1C and PdG levels were approximately parallel to plasma E2 and P levels, respectively. The E1C profiles of daily urinary and fecal samples revealed a midcycle peak, followed by a sustained PdG increase lasting up to two weeks from the E1C peak. A fecal E1C peak was one day later than the urinary E1C peak. One of the captive females exhibited a discrete plasma LH peak, one indicator that ovulation has occurred, on the day following the urinary E1C peak, i.e., the same day of fecal E1C peak. We measured excreted steroids in nine wild females and determined the timing of ovulation by comparing fecal steroid profiles to those obtained in captive monkeys. Data from wild females indicated that eight of nine females conceived during their first ovulatory cycle of the sampling period, whereas the remaining female failed to conceive during the sampling period even though she ovulated. In the eight females that conceived, E1C increased again following the detected or estimated E1C peak, with levels comparable to the preovulatory peak levels, and sustained elevations of PdG for over 40 days. These data illustrate that the urinary and fecal profiles of ovarian steroid excretion obtained through the application of these noninvasive techniques provide an accurate approach for monitoring conceptive and nonconceptive ovarian cycle in captive and free-living Japanese macaques.